The following message appears while attempting to export to excel (xls).
This issue is caused by an Excel 2003 or earlier limitation. EminentWare plans to address this issue by including the ability to export in xlsx format. This feature is being reviewed for possible inclusion with the release of 1.70 SP2.
A potential workaround here is to export to .CSV or .XML and then import that into Excel, as those formats do not share the same limitation.